Update of the vitamin D content of fortified foods and supplements in the UK National Diet and Nutrition Survey Nutrient Databank

Abstract

Food composition tables require updating regularly to keep abreast of the periodic reformulation of fortified foods and dietary supplements. This paper describes a process undertaken to update the vitamin D content of fortified foods and supplements consumed in the UK, and the impact this may have on reported vitamin D intake. In 2011, the vitamin D content of the 289 vitamin D fortified foods and vitamin D containing supplements recorded in the National Diet and Nutrition Survey (NDNS) Nutrient Databank (last updated in 2008) was compared to data from industry websites, trade associations and manufacturers, and nutrition labelling on pack. Typical ‘overages’ (the additional amount added to account for any processing loss or degradation) applied during vitamin D fortification were also obtained. This information was used to update the NDNS Nutrient Databank, and applied to NDNS food consumption data (2008/2010) to determine the impact of the composition update on reported population vitamin D intakes. Up-to-date vitamin D values were obtained for 257 (89%) of the 289 items in the NDNS databank; the remainder were no longer available on the market. The vitamin D content of 31 (11%) of the items had changed, and these were most commonly breakfast cereals, fat spreads and powdered malt drinks. A further eight food items were identified as newly fortified with vitamin D. Calculation of mean vitamin D intakes using updated data identified that use of out-of-date food composition data may lead to an underestimation of UK vitamin D intakes of around 3% (0.1 μg/day). When a blanket 12.5% ‘overage’ was applied to all items, this underestimate increased to 6% (0.2 μg/day). Even though the absolute impact of updating the vitamin D content of fortified foods and supplements on population mean intakes is relatively small, our analysis suggests it is important that nutrient databases are regularly updated. The new estimates of the vitamin D content of foods and supplements should be used for future estimates of vitamin D intake in the UK until a further periodic update is conducted.